Around 50 protesters dressed in wetsuits, backed by 1,000 supporters, managed to hold up the cruise ships by over an hour as they paddled in the canal – some armed with inflatable rings.

The protest was timed to coincide with a busy day on the canal, as a scheduling quirk meant 12 cruise ships were due to head past St Mark’s Square – well above the daily average of two ships.

“The demonstration was a great success and we now hope the government will take advantage of this momentum and kick the cruise ships out of the Venice lagoon,” said Silvio Testa, a spokesman for the protesters.